The invention concerns a burner with an integrated electric igniter and a burner-flame monitor for gaseous fuels and oxygen. One field of application for the burner is to generate gases that contain CO and H.sub.2 by partly oxidizing gaseous hydrocarbons in a pressurized reactor. Another application for the burner is as a pilot or backup burner in a reactor for gasifying powdered and/or liquid fuels by partly oxidizing them with oxygen. The resulting CO--and H.sub.2 -containing gases are employed as synthesis, hydrogenation, municipal-supply, and metallurgical-reduction gases and for similar purposes.
DD Patent No. 241 457 describes a generic burner for partly oxidizing gaseous hydrocarbons into gases that contain CO and H.sub.2 in a pressurized reactor. An ignition pipe is positioned in a fuel-gas channel, is electrically insulated from the metal wall of the channel, and is connected to the high-voltage end of an electric high-voltage igniter. The end of the igniter that is inside the channel and faces the reaction zone has a pin-type electrode aimed at the wall of the channel, creating a spark gap. The ignition pipe also communicates by way of a shut-off valve with a source of oxygen and has oxygen outlets in the vicinity of the spark gap.
The burner's fuel-gas channel consists of a cylindrical section followed toward the reaction zone by a confusor and by a narrower cylindrical fuel-gas outlet nozzle. The fuel-gas channel is demarcated by the metal wall from a surrounding annular oxygen channel, and the ignition pipe is positioned eccentrically in the channel with its reaction-zone end and electrode upstream of the fuel-gas outlet nozzle.
Some of the outlets in the ignition pipe are upstream of the electrode and face the metal channel wall. Since the reaction-zone end of the ignition pipe also has outlets, some of the oxygen leaves the radial axially.
One drawback of an igniter accommodated inside the fuel-gas channel in this way is that it cannot be employed to ignite the actual burner flame, but only an ancillary flame that itself then ignites the main flame. Since oxygen must be introduced into the fuel-gas channel to generate the ancillary flame, explosive ignition and local overheating, leading to premature wear, cannot be ruled out.
The need to ignite an ancillary flame also increases the number of sources of malfunction that can occur as the system is started up and accordingly limits its reliability.
Another drawback of this approach is that it necessitates an additional oxygen intake for igniting the flame. Although this intake is active only during the ignition, it must still be sealed off from the atmosphere and monitored at the pressure end, endtailing additional expenditures for machinery and safety engineering.
The system described in DD WP 241 457 can also be started up by the igniter in the fuel-gas channel only once the reactor has been depressurized, which also limits its application.